(It is interesting that ioscan does not report /dev/my_device. Is that
indicative of a problem? If so, what?)

So...I don't understand. The kernel is forming a dev_t value and passing it
to my ioctl() routine (or open(), or close()). However when I attempt to use
WSIO to get an isc pointer from that dev_t value, the returned pointer
is NULL. The FAQ implies that this is because the dev_t value was somehow
invalid.

What am I not understanding here?

Any insights would be greatly appreciated. Thanks.

Jimmie

(Sorry about the long-winded post. I've wasted a day pursing this problem
and I feel I'm no closer to the answer now than I was when I started. As
an aside, I have to admit driver development for Solaris and in fact Linux
is a lot less frustrating than it has been for HP-UX. There's so little
useful HP-UX information available that it seems HP is trying to discourage
driver developers from targetting their platform).

2> Try calling wsio_get_isc(dev, &isc, NULL) with wsio.h included.
This will work only if your driver is char driver.

--vishwas

Re: Device driver: wsio_get_isc() returns NULL

> That leads to another question though:
>
> 1) What is the significance of the classname in the drv_info_t structure?
>
> The DLKM appeared to get initialized properly even with the bad
> classname string. That is, the attach() function was called, the 'isc'
> was claimed and I was able to use that isc to read and write the
> card's register space. No errors were reported by WSIO or any other
> kernel routine.
>
> Problems didn't occur until I started to do things from user space.
> The kernel called my driver routines (open, close, ioctl, etc) when the
> user space app accessed the corresponding /dev entry which suggests that
> the kernel has properly mapped the device major to my driver. But the
> bad classname string somehow caused the kernel to fail to map the dev_t
> to the isc. This still confuses me.
>
> It seems to me that if the classname were such an crucial piece
> of information, WSIO should have thrown an error as soon as my driver
> tried to claim the isc in the attach() routine.
>

AFAIK class should be one of the known class strings or unknown.
Yes, WSIO should have reported an error if the class was not
acceptable.